1. Field of the Invention
This invention relates to connectors for cable, such as coaxial cable and, more particularly, to a compression tool for operatively attaching a connector to the cable. The invention is also directed to a method of using such a compression tool.
2. Background Art
Connectors are operatively attached to cables used for a multitude of purposes in many different environments. A particularly high volume of such connectors is attached to coaxial cable for its various applications. The coaxial cable may be sold with pre-attached connectors, thereby requiring connector attaching tools at a cable manufacturing facility, or a separate facility at which the cable is staged for attachment of the connectors. These tools must be capable of consistently and reliably attaching the connectors on a high volume basis. Stationary, non-portable tools may be provided for this purpose, as shown for example in U.S. Pat. No. 6,116,069, to Holliday. Since portability is not a concern, tools of this type can be made with high strength, and potentially heavy, components with the ability to produce a large compressive attaching force, as in a direction parallel to the cable length, between connector parts.
More commonly, cable is cut to length and connectors attached thereto in the field. This process may be carried out by a homeowner, but is performed on a much greater volume by professionals that move from site to site to effect repairs and/or installations of equipment requiring coaxial cable connection.
Portable compression and crimping tools used for this purpose are available with different capacity and quality. A homeowner may purchase such a tool, adequate to meet limited demands, relatively inexpensively. Tools of this type are generally constructed with mechanical components that rely upon the application of a significant gripping force by a user for their successful operation. The nature and quality of the connection is dictated by the particular application force produced through this gripping action. Inconsistent force application may result in connections with different integrity. It may be impossible for certain individuals to reliably generate a force of sufficient magnitude that will adequately maintain the attachment of certain connectors to a cable. Users with the requisite hand strength may eventually suffer from fatigue after repeated use of the tools, whereby the quality of the connections may eventually suffer. Such basic tools thus become impractical for professional users that may be required to attach a multitude of connectors in the course of a day.
While higher end tools with greater mechanical advantage are available to professionals, a number of the above problems still persist. Failed or compromised connections can have a significant financial impact on a business if experienced in any significant volume. In the highly competitive cable industry, where margins for installations are relatively small, such failures not only necessitate follow up visits and repairs, but may also significantly impact the reputation of the installing company.
The above problems are aggravated by the fact that many new types of connectors are requiring even greater attaching forces, particularly those that must be attached using compression tools that exert compressive forces aligned lengthwise/axially with respect to the cable. So long as the integrity of the connector attachment depends upon the degree of force applied by the user, and the available tools permit inconsistent force application, the above problems, particularly inconsistent quality and user fatigue, will persist.
Tools for attaching cable connectors, that are operable using mechanical assistance, are known. It is known to apply connecting forces hydraulically or pneumatically on equipment at a fixed location in a manufacturing facility, as seen for example in U.S. Pat. No. 6,116,069, to Holliday.
It is also known to hydraulically and pneumatically drive crimping tool components on units that are portable in nature to exert radial crimping forces on connectors, as shown for example in U.S. Pat. No. 4,774,762, to Gobeil. This tool is limited to producing radial crimping forces and is also relatively complicated in nature. This makes this type of equipment generally expensive and prone to failure. It may thus be impractical for use on a high volume basis for on site installations.
In spite of its maturity, the industry has not developed a feasible compression tool construction that mechanically assists the application of axial connecting forces and has a geometry that makes transportation thereof and on site use practical on a high volume basis. Thus, for on site applications, the industry has continued to use the basic hand held tool that relies solely upon forces generated by a user's hand(s).